• Thijs, Leon C.
• Van Oijen, Jeroen A.
• De Goey, Philip
• Van Gool, Catharina Elisabeth Adriana Gerardus
• Ramaekers, W. J. S.

Abstract

Flame propagation of iron powder in air is numerically studied. The present work introduces a chemical equilibrium model, which allows a detailed representation of the combustion products, phase transitions and detailed thermodynamics of the condensed phase. First, to validate the combustion of a single particle, numerical laser ignited single particle studies are performed and compared to experiments, where a very good agreement is obtained. A second series of simulations is performed on the propagation of laminar flames in iron/air mixtures for a wide range of equivalence ratios (φ = 0.2–1.8) using mono-dispersed particles having a diameter of 10 µm. Based on these simulations a multi-staged combustion process is identified, where each stage can be related to the formation of a different oxide. More importantly, the significance of including at least Fe₃O₄ in the model is demonstrated. This species contributes significantly to the burning velocity and flame temperature, as it is responsible for more than 25% of the total energy which can be released.

Topics

• impedance spectroscopy
• phase
• experiment
• simulation
• phase transition
• combustion
• iron
• iron powder